FAILED: patch "[PATCH] ceph: fix writeback_count leak in write_folio_nounlock()" failed to apply to 6.6-stable tree

index 61bd6d92ff25..ecf33b66610c 100644
@@ -790,6 +790,9 @@ static int write_folio_nounlock(struct folio *folio,
 				    ceph_wbc.truncate_size, true);
 	if (IS_ERR(req)) {
 		folio_redirty_for_writepage(wbc, folio);
+		if (atomic_long_dec_return(&fsc->writeback_count) <
+				CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+			fsc->write_congested = false;
 		return PTR_ERR(req);
 	}
 

@@ -809,6 +812,9 @@ static int write_folio_nounlock(struct folio *folio,
 			folio_redirty_for_writepage(wbc, folio);
 			folio_end_writeback(folio);
 			ceph_osdc_put_request(req);
+			if (atomic_long_dec_return(&fsc->writeback_count) <
+					CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+				fsc->write_congested = false;
 			return PTR_ERR(bounce_page);
 		}
 	}

@@ -847,6 +853,9 @@ static int write_folio_nounlock(struct folio *folio,
 			      ceph_vinop(inode), folio);
 			folio_redirty_for_writepage(wbc, folio);
 			folio_end_writeback(folio);
+			if (atomic_long_dec_return(&fsc->writeback_count) <
+					CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+				fsc->write_congested = false;
 			return err;
 		}
 		if (err == -EBLOCKLISTED)

index db4d11604e9d5..603adf1d590e3 100644
@@ -799,32 +799,6 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 	return err;
 }
 
-static int ceph_writepage(struct page *page, struct writeback_control *wbc)
-{
-	int err;
-	struct inode *inode = page->mapping->host;
-	BUG_ON(!inode);
-	ihold(inode);
-
-	if (wbc->sync_mode == WB_SYNC_NONE &&
-	    ceph_inode_to_fs_client(inode)->write_congested) {
-		redirty_page_for_writepage(wbc, page);
-		return AOP_WRITEPAGE_ACTIVATE;
-	}
-
-	wait_on_page_fscache(page);
-
-	err = writepage_nounlock(page, wbc);
-	if (err == -ERESTARTSYS) {
-		/* direct memory reclaimer was killed by SIGKILL. return 0
-		 * to prevent caller from setting mapping/page error */
-		err = 0;
-	}
-	unlock_page(page);
-	iput(inode);
-	return err;
-}
-
 /*
  * async writeback completion handler.
  *

@@ -1563,7 +1537,6 @@ static int ceph_write_end(struct file *file, struct address_space *mapping,
 const struct address_space_operations ceph_aops = {
 	.read_folio = netfs_read_folio,
 	.readahead = netfs_readahead,
-	.writepage = ceph_writepage,
 	.writepages = ceph_writepages_start,
 	.write_begin = ceph_write_begin,
 	.write_end = ceph_write_end,

@@ -1571,6 +1544,7 @@ const struct address_space_operations ceph_aops = {
 	.invalidate_folio = ceph_invalidate_folio,
 	.release_folio = ceph_release_folio,
 	.direct_IO = noop_direct_IO,
+	.migrate_folio = filemap_migrate_folio,
 };
 
 static void ceph_block_sigs(sigset_t *oldset)

index 603adf1d590e3..95b3e6b1c11aa 100644
@@ -1659,8 +1659,8 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_file_info *fi = vma->vm_file->private_data;
 	struct ceph_cap_flush *prealloc_cf;
-	struct page *page = vmf->page;
-	loff_t off = page_offset(page);
+	struct folio *folio = page_folio(vmf->page);
+	loff_t off = folio_pos(folio);
 	loff_t size = i_size_read(inode);
 	size_t len;
 	int want, got, err;

@@ -1677,10 +1677,10 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
 	sb_start_pagefault(inode->i_sb);
 	ceph_block_sigs(&oldset);
 
-	if (off + thp_size(page) <= size)
-		len = thp_size(page);
+	if (off + folio_size(folio) <= size)
+		len = folio_size(folio);
 	else
-		len = offset_in_thp(page, size);
+		len = offset_in_folio(folio, size);
 
 	dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n",
 	     inode, ceph_vinop(inode), off, len, size);

@@ -1697,30 +1697,30 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
 	dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",
 	     inode, off, len, ceph_cap_string(got));
 
-	/* Update time before taking page lock */
+	/* Update time before taking folio lock */
 	file_update_time(vma->vm_file);
 	inode_inc_iversion_raw(inode);
 
 	do {
 		struct ceph_snap_context *snapc;
 
-		lock_page(page);
+		folio_lock(folio);
 
-		if (page_mkwrite_check_truncate(page, inode) < 0) {
-			unlock_page(page);
+		if (folio_mkwrite_check_truncate(folio, inode) < 0) {
+			folio_unlock(folio);
 			ret = VM_FAULT_NOPAGE;
 			break;
 		}
 
-		snapc = ceph_find_incompatible(page);
+		snapc = ceph_find_incompatible(&folio->page);
 		if (!snapc) {
-			/* success.  we'll keep the page locked. */
-			set_page_dirty(page);
+			/* success.  we'll keep the folio locked. */
+			folio_mark_dirty(folio);
 			ret = VM_FAULT_LOCKED;
 			break;
 		}
 
-		unlock_page(page);
+		folio_unlock(folio);
 
 		if (IS_ERR(snapc)) {
 			ret = VM_FAULT_SIGBUS;

index 95b3e6b1c11aa..9472e9f25dab0 100644
@@ -1391,23 +1391,23 @@ static int context_is_writeable_or_written(struct inode *inode,
 
 /**
  * ceph_find_incompatible - find an incompatible context and return it
- * @page: page being dirtied
+ * @folio: folio being dirtied
  *
- * We are only allowed to write into/dirty a page if the page is
+ * We are only allowed to write into/dirty a folio if the folio is
  * clean, or already dirty within the same snap context. Returns a
  * conflicting context if there is one, NULL if there isn't, or a
  * negative error code on other errors.
  *
- * Must be called with page lock held.
+ * Must be called with folio lock held.
  */
 static struct ceph_snap_context *
-ceph_find_incompatible(struct page *page)
+ceph_find_incompatible(struct folio *folio)
 {
-	struct inode *inode = page->mapping->host;
+	struct inode *inode = folio->mapping->host;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 
 	if (ceph_inode_is_shutdown(inode)) {
-		dout(" page %p %llx:%llx is shutdown\n", page,
+		dout(" folio %p %llx:%llx is shutdown\n", folio,
 		     ceph_vinop(inode));
 		return ERR_PTR(-ESTALE);
 	}

@@ -1415,29 +1415,29 @@ ceph_find_incompatible(struct page *page)
 	for (;;) {
 		struct ceph_snap_context *snapc, *oldest;
 
-		wait_on_page_writeback(page);
+		folio_wait_writeback(folio);
 
-		snapc = page_snap_context(page);
+		snapc = page_snap_context(&folio->page);
 		if (!snapc || snapc == ci->i_head_snapc)
 			break;
 
 		/*
-		 * this page is already dirty in another (older) snap
+		 * this folio is already dirty in another (older) snap
 		 * context!  is it writeable now?
 		 */
 		oldest = get_oldest_context(inode, NULL, NULL);
 		if (snapc->seq > oldest->seq) {
 			/* not writeable -- return it for the caller to deal with */
 			ceph_put_snap_context(oldest);
-			dout(" page %p snapc %p not current or oldest\n", page, snapc);
+			dout(" folio %p snapc %p not current or oldest\n", folio, snapc);
 			return ceph_get_snap_context(snapc);
 		}
 		ceph_put_snap_context(oldest);
 
-		/* yay, writeable, do it now (without dropping page lock) */
-		dout(" page %p snapc %p not current, but oldest\n", page, snapc);
-		if (clear_page_dirty_for_io(page)) {
-			int r = writepage_nounlock(page, NULL);
+		/* yay, writeable, do it now (without dropping folio lock) */
+		dout(" folio %p snapc %p not current, but oldest\n", folio, snapc);
+		if (folio_clear_dirty_for_io(folio)) {
+			int r = writepage_nounlock(&folio->page, NULL);
 			if (r < 0)
 				return ERR_PTR(r);
 		}

@@ -1452,7 +1452,7 @@ static int ceph_netfs_check_write_begin(struct file *file, loff_t pos, unsigned
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_snap_context *snapc;
 
-	snapc = ceph_find_incompatible(folio_page(*foliop, 0));
+	snapc = ceph_find_incompatible(*foliop);
 	if (snapc) {
 		int r;
 

@@ -1712,7 +1712,7 @@ static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
 			break;
 		}
 
-		snapc = ceph_find_incompatible(&folio->page);
+		snapc = ceph_find_incompatible(folio);
 		if (!snapc) {
 			/* success.  we'll keep the folio locked. */
 			folio_mark_dirty(folio);

index 9472e9f25dab0..57086663a9bf9 100644
@@ -652,21 +652,22 @@ static u64 get_writepages_data_length(struct inode *inode,
 }
 
 /*
- * Write a single page, but leave the page locked.
+ * Write a folio, but leave it locked.
  *
  * If we get a write error, mark the mapping for error, but still adjust the
- * dirty page accounting (i.e., page is no longer dirty).
+ * dirty page accounting (i.e., folio is no longer dirty).
  */
-static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
+static int write_folio_nounlock(struct folio *folio,
+		struct writeback_control *wbc)
 {
-	struct folio *folio = page_folio(page);
-	struct inode *inode = page->mapping->host;
+	struct page *page = &folio->page;
+	struct inode *inode = folio->mapping->host;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
 	struct ceph_snap_context *snapc, *oldest;
-	loff_t page_off = page_offset(page);
+	loff_t page_off = folio_pos(folio);
 	int err;
-	loff_t len = thp_size(page);
+	loff_t len = folio_size(folio);
 	loff_t wlen;
 	struct ceph_writeback_ctl ceph_wbc;
 	struct ceph_osd_client *osdc = &fsc->client->osdc;

@@ -674,25 +675,25 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 	bool caching = ceph_is_cache_enabled(inode);
 	struct page *bounce_page = NULL;
 
-	dout("writepage %p idx %lu\n", page, page->index);
+	dout("writepage %p idx %lu\n", folio, folio->index);
 
 	if (ceph_inode_is_shutdown(inode))
 		return -EIO;
 
 	/* verify this is a writeable snap context */
-	snapc = page_snap_context(page);
+	snapc = page_snap_context(&folio->page);
 	if (!snapc) {
-		dout("writepage %p page %p not dirty?\n", inode, page);
+		dout("writepage %p folio %p not dirty?\n", inode, folio);
 		return 0;
 	}
 	oldest = get_oldest_context(inode, &ceph_wbc, snapc);
 	if (snapc->seq > oldest->seq) {
-		dout("writepage %p page %p snapc %p not writeable - noop\n",
-		     inode, page, snapc);
+		dout("writepage %p folio %p snapc %p not writeable - noop\n",
+		     inode, folio, snapc);
 		/* we should only noop if called by kswapd */
 		WARN_ON(!(current->flags & PF_MEMALLOC));
 		ceph_put_snap_context(oldest);
-		redirty_page_for_writepage(wbc, page);
+		folio_redirty_for_writepage(wbc, folio);
 		return 0;
 	}
 	ceph_put_snap_context(oldest);

@@ -709,8 +710,8 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 		len = ceph_wbc.i_size - page_off;
 
 	wlen = IS_ENCRYPTED(inode) ? round_up(len, CEPH_FSCRYPT_BLOCK_SIZE) : len;
-	dout("writepage %p page %p index %lu on %llu~%llu snapc %p seq %lld\n",
-	     inode, page, page->index, page_off, wlen, snapc, snapc->seq);
+	dout("writepage %p folio %p index %lu on %llu~%llu snapc %p seq %lld\n",
+	     inode, folio, folio->index, page_off, wlen, snapc, snapc->seq);
 
 	if (atomic_long_inc_return(&fsc->writeback_count) >
 	    CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))

@@ -722,32 +723,32 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 				    ceph_wbc.truncate_seq,
 				    ceph_wbc.truncate_size, true);
 	if (IS_ERR(req)) {
-		redirty_page_for_writepage(wbc, page);
+		folio_redirty_for_writepage(wbc, folio);
 		return PTR_ERR(req);
 	}
 
 	if (wlen < len)
 		len = wlen;
 
-	set_page_writeback(page);
+	folio_start_writeback(folio);
 	if (caching)
-		ceph_set_page_fscache(page);
+		ceph_set_page_fscache(&folio->page);
 	ceph_fscache_write_to_cache(inode, page_off, len, caching);
 
 	if (IS_ENCRYPTED(inode)) {
-		bounce_page = fscrypt_encrypt_pagecache_blocks(page,
+		bounce_page = fscrypt_encrypt_pagecache_blocks(&folio->page,
 						    CEPH_FSCRYPT_BLOCK_SIZE, 0,
 						    GFP_NOFS);
 		if (IS_ERR(bounce_page)) {
-			redirty_page_for_writepage(wbc, page);
-			end_page_writeback(page);
+			folio_redirty_for_writepage(wbc, folio);
+			folio_end_writeback(folio);
 			ceph_osdc_put_request(req);
 			return PTR_ERR(bounce_page);
 		}
 	}
 
 	/* it may be a short write due to an object boundary */
-	WARN_ON_ONCE(len > thp_size(page));
+	WARN_ON_ONCE(len > folio_size(folio));
 	osd_req_op_extent_osd_data_pages(req, 0,
 			bounce_page ? &bounce_page : &page, wlen, 0,
 			false, false);

@@ -771,24 +772,24 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 			wbc = &tmp_wbc;
 		if (err == -ERESTARTSYS) {
 			/* killed by SIGKILL */
-			dout("writepage interrupted page %p\n", page);
-			redirty_page_for_writepage(wbc, page);
-			end_page_writeback(page);
+			dout("writepage interrupted folio %p\n", folio);
+			folio_redirty_for_writepage(wbc, folio);
+			folio_end_writeback(folio);
 			return err;
 		}
 		if (err == -EBLOCKLISTED)
 			fsc->blocklisted = true;
-		dout("writepage setting page/mapping error %d %p\n",
-		     err, page);
+		dout("writepage setting mapping error %d %p\n",
+		     err, folio);
 		mapping_set_error(&inode->i_data, err);
 		wbc->pages_skipped++;
 	} else {
-		dout("writepage cleaned page %p\n", page);
+		dout("writepage cleaned folio %p\n", folio);
 		err = 0;  /* vfs expects us to return 0 */
 	}
-	oldest = detach_page_private(page);
+	oldest = folio_detach_private(folio);
 	WARN_ON_ONCE(oldest != snapc);
-	end_page_writeback(page);
+	folio_end_writeback(folio);
 	ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
 	ceph_put_snap_context(snapc);  /* page's reference */
 

@@ -1437,7 +1438,7 @@ ceph_find_incompatible(struct folio *folio)
 		/* yay, writeable, do it now (without dropping folio lock) */
 		dout(" folio %p snapc %p not current, but oldest\n", folio, snapc);
 		if (folio_clear_dirty_for_io(folio)) {
-			int r = writepage_nounlock(&folio->page, NULL);
+			int r = write_folio_nounlock(folio, NULL);
 			if (r < 0)
 				return ERR_PTR(r);
 		}

index 57086663a9bf9..c63ed9fa1ccd7 100644
@@ -724,6 +724,9 @@ static int write_folio_nounlock(struct folio *folio,
 				    ceph_wbc.truncate_size, true);
 	if (IS_ERR(req)) {
 		folio_redirty_for_writepage(wbc, folio);
+		if (atomic_long_dec_return(&fsc->writeback_count) <
+				CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+			fsc->write_congested = false;
 		return PTR_ERR(req);
 	}
 

@@ -743,6 +746,9 @@ static int write_folio_nounlock(struct folio *folio,
 			folio_redirty_for_writepage(wbc, folio);
 			folio_end_writeback(folio);
 			ceph_osdc_put_request(req);
+			if (atomic_long_dec_return(&fsc->writeback_count) <
+					CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+				fsc->write_congested = false;
 			return PTR_ERR(bounce_page);
 		}
 	}

@@ -775,6 +781,9 @@ static int write_folio_nounlock(struct folio *folio,
 			dout("writepage interrupted folio %p\n", folio);
 			folio_redirty_for_writepage(wbc, folio);
 			folio_end_writeback(folio);
+			if (atomic_long_dec_return(&fsc->writeback_count) <
+					CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+				fsc->write_congested = false;
 			return err;
 		}
 		if (err == -EBLOCKLISTED)